Growth is a permanent and an irreversible change in the volume or size and an increase in dry weight of a living body . Growth is the net result of active metabolism . In general , growth may be defined as a vital process which brings about a permanent change in any plant or its part in respect to size , form , weight and volume.
Plant Hormones or Phytohormones
Plant hormones are organic compounds ,produced within the plant body and regulate growth and development . They usually move from the site of production to the site of action . They are mainly produced in apical bud , young leaves ,root tip , embryo , etc . Some of the important characters of hormones are as follows :-
- Growth hormones are usually produced at the apices of roots , stems and leaves.
- They are transported to other parts of the plants through phloem .
- They promote growth in very low concentration.
- They all are organic in nature.
- They are used in extremely small amount . The phytohormones are of following types :- 1. Auxin 2. Gibberellins 3. Cytokinins 4. Ethylene 5. Abscissic Acid ( ABA)